Bool.hpp

#pragma once
 
#include "util/Assert.hpp"
#include "util/prometheus/Gauge.hpp"
 
#include <cstdint>
#include <functional>
 
namespace util::prometheus {
 
template <typename T>
concept SomeBoolImpl = requires(T a) {
    { a.set(0) } -> std::same_as<void>;
    { a.value() } -> std::same_as<int64_t>;
};

template <SomeBoolImpl ImplType>
class AnyBool {
    std::reference_wrapper<ImplType> impl_;
 
public:
    explicit AnyBool(ImplType& impl) : impl_(impl)
    {
    }

    AnyBool&
    operator=(bool value)
    {
        impl_.get().set(value ? 1 : 0);
        return *this;
    }

    operator bool() const
    {
        auto const value = impl_.get().value();
        ASSERT(value == 0 || value == 1, "Invalid value for bool: {}", value);
        return value == 1;
    }
};

using Bool = AnyBool<GaugeInt>;
 
}  // namespace util::prometheus